中文摘要：

考虑四辊轧机在轧制过程中液压压下缸和平衡缸的非线性弹性约束作用,建立轧机辊系的多分段非线性动力学方程。运用平均法求解系统的频率响应方程,并采用奇异性理论分析系统的分岔行为,得到系统的转迁集以及6组不同的分岔图。以轧机实际参数为例,分析各非线性参数对系统幅频特性曲线的影响,发现系统幅频曲线在各分段处具有向高频段拐弯的特性,适当选取系统参数可有效减小这种行为的发生,这为抑制轧机辊系振动提供了理论参考。

英文摘要：

Considering the role of nonlinear elastic constraint of the hydraulic pressure cylinder and compensating cylinder in the four-high rolling mill process,a multi-segmented nonlinear vibration dynamic equation of rolling mill rolls is established.Averaging method is used to get frequency response equation of the system,singularity theory is applied to analysis it and then 6 group transition sets and bifurcation diagrams are obtained,which show the various bifurcation forms of this system.The actual parameters of rolling mill is used to analyze the impact law that every nonlinear parameter on vibration characteristics of this system,after the numerical simulation the characteristics that the amplitude-frequency characteristic curves both show turning to the high frequency in each segment are found.Choosing proper system parameter can restrain this behave effectively,which provides a theoretical basis to suppress vibration of rolling mill rolls.